maint: Replace unnecessary tabs with spaces. * doc/interpreter/images.awk, libinterp/dldfcn/config-module.awk, libinterp/octave-value/module.mk, m4/module.mk, scripts/java/org/octave/Matrix.java, scripts/miscellaneous/module.mk, scripts/sparse/module.mk, scripts/startup/main-rcfile, test/build-sparse-tests.sh, test/ctor-vs-method/@parent/parent.m: maint: Replace unnecessary tabs with spaces.

EXTRA_DIST += \
  m4/module.mk \
  m4/ax_blas.m4 \
  m4/ax_blas_f77_func.m4 \
  m4/ax_compare_version.m4 \
  m4/ax_lapack.m4 \
  m4/ax_pthread.m4 \
  m4/gnulib-cache.m4 \
  m4/libtool.m4 \
  m4/ltoptions.m4 \
  m4/ltsugar.m4 \
  m4/ltversion.m4 \
  m4/lt~obsolete.m4 \
  m4/pkg.m4